1. Field of the Invention
The present invention relates to treadmill for physical therapy and more particularly, to such a medical gymnastic treadmill that allows synchronous adjustment of the height of the two handrails.
2. Description of the Related Art
A medical gymnastic treadmill is designed for a person having an injured leg or a patient not able to move freely to stand, walk or run upon. During the therapy course, a therapist may help the patient perform the exercise. However, in most time the patient must stand upon the tread belt of the treadmill by oneself so that the desired therapy effect is achievable. Therefore, a medical gymnastic treadmill has two handrails provided at two opposite lateral sides for the gripping of the user's hands during exercise. However, because different users have different body sizes, handrails of fixed height cannot suit and fit all users of different sizes. In order to fit different users, the length and width of the handrails of a medical gymnastic treadmill should be adjustable so that every user can use the machine safely without causing a secondary injury.
Many medical gymnastic treadmills with height-adjustable handrails are commercially available. U.S. Pat. No. 4,708,337 discloses a treadmill entitled “Automatic Treadmill, in which each handrail consists of an tube and an sleeve clamped by a nut, and a grip is provided on the sleeve touching the tapered portion of the nut. When the nut is turned loose, the grip on the sleeve is released. Thus, the tube and sleeve may be moved relative to each other to adjust the height of the handrail. After the desired height is reached, one can turn tight the nut for a tight fit between the inner and sleeves. This adjustment procedure is complicated and requires much time and labor. Further, it is difficult to adjust the two handrails to the same height.
Therefore, it is desirable to provide a medical gymnastic treadmill that eliminates the aforesaid problems.